Automated systems have been developed over the years to replace and improve over known methods of applying paint using a brush, roller, or blade. Spray guns are often used to apply paint in a uniform coat or to cover large surface areas rapidly. Spray guns may be air-operated where a reservoir or compressor sends compressed air in the gun after being mixed in a desired proportion with paint to be sprayed onto a surface. Other spray guns are airless, where the spray is driven by pressurized paint routed to the nozzle area of a spray gun. Paint is generally stored in a container and is attached via a tube to the spray gun. Other types of spray guns include high volume/low pressure (HVLP) and electrostatic guns. A pumping means, such as an electrically driven or hydraulically operated pump, transports paint from the storage location to the nozzle of the spray gun. Spray guns are equipped with a release mechanism, generally in the form of a trigger.
The nozzle device is conveniently designed to be adapted to the shape of a hand-held gun. These guns are also frequently equipped for robots, which may be programmed to distribute and spread the paint over a surface more evenly than a person. Paint can be applied in solid form, such as a powder, or as a gaseous suspension, such as an aerosol or liquid. Since paint is designed to solidify if left unattended through evaporation of a solvent suspended in the paint, the painting equipment, such as spray guns, must be cleaned between applications in preparation for later reuse. Unlike petroleum-based paints, water-based paints are generally easier to dissolve in most solvents because water-based paints undergo a process of polymerization and do not dissolve when cleaning.
Manual and automatic systems have been devised to clean both the inside and outside of spray guns. Manual cleaning of spray guns is labor intensive and generates significant quantities of solvent waste. Automatic cleaning systems for spray guns are similar to conventional home dishwashing machines, except that the thinners and solvents to be used cannot be heated in the process due to the volatility of solvents. Automatic paint gun washers can reduce the amount of solvent used and paint solvent waste generated by up to 70-80% in comparison to manual paint gun cleaning. Petroleum-based paints, which can be dissolved readily, require less mechanical activity to remove dried paint, whereas water-based paints require high-pressure friction to remove dried paint. The solvents used to dissolve petroleum-based paints are generally more abrasive, less environment friendly, and require containment, storage, and filtration. Furthermore, the washing unit must be sealed. FIG. 1 shows an automated spray gun equipment device for petroleum-based paints found in the prior art.
What is needed is a water-based cleaning agent that may be used in conjunction with a water-based automated washing device and/or with a water-based spray gun and a method of cleaning the device that is both environmentally friendly and possesses sufficient cleaning capacity to operate as a dissolving mechanism for water-based paints.